Full-text searching in Perl

I've had to build several full-text search engines recently, and found that Perl works extremely well for this. Not only can Perl easily read and manipulate text files, Perl also has built-in support for fast B-Tree databases. In this article, I'll present some Perl programs that handle very rapid Ill-text searching. With a little work, you could easily use these programs to provide full-text search capability for a web site.